NEO-M8N GPS module: specs and pinout
A u-blox NEO-M8N concurrent GNSS receiver (GPS, GLONASS, BeiDou, Galileo) module with UART, USB, SPI and I2C-compatible DDC interfaces; the listing adds an active ceramic antenna. The listing board is not confirmed to carry a genuine u-blox NEO-M8N (look-alike receivers are sold under this name).
Specs
| Spec | Value | Source |
|---|---|---|
| Supply voltage VCC (NEO-M8N) | 2.7 V min, 3.0 V typ, 3.6 V max | source Table 10 Operating conditions (p.18) |
| Operating temperature | -40 to 85 C | source Table 10 (p.19) |
| Interfaces | UART, USB, SPI, DDC (I2C compliant) | source Section 1.2 table (p.5); Section 1.17 (p.12) |
| Default UART | 9600 baud, 8 bits, no parity, 1 stop bit | source Section 8 Default messages (p.25) |
| Horizontal position accuracy | 2.5 m CEP (GPS and GLONASS); 2.0 m with SBAS | source Table 1 (p.6) |
| Max navigation update rate | 5 Hz (GPS and GLONASS concurrent); 10 Hz single constellation | source Table 1 (p.6) |
| Tracking current, continuous mode | 30 mA typ GPS and GLONASS; 23 mA typ GPS only (3.0 V) | source Table 11 (p.19) |
| Maximum supply current | 67 mA | source Table 11 (p.19) |
| Active antenna recommendation | Minimum gain 15 dB; maximum noise figure 1.5 dB | source Table 5 (p.14) |
| Digital input high level VIH | 0.7 x VCC min | source Table 10 (p.18) |
Power
| Value | Source | |
|---|---|---|
| Supply | VCC 2.7-3.6 V (chip module) | source Table 11 (p.19) |
| Current | 30 mA typ tracking GPS and GLONASS at 3.0 V; 67 mA max | source Table 11 (p.19) |
Chip pins
These are the pins of the chip on the module, from the chip datasheet. The module's own header may label or expose them differently.
Pins above are the u-blox NEO-M8N 24-pin module pins. The listing breakout board (header order, regulator, antenna connector, level shifting) is not covered by an official document.
| Pin | Function | Voltage | Notes | Source |
|---|---|---|---|---|
| VCC | Supply voltage | 2.7-3.6 V | Module pin 23 | source Table 6 (p.15) |
| GND | Ground | Pins 10, 12, 13, 24 | source Table 6 (p.15) | |
| TXD / SPI MISO | Serial port out if D_SEL = 1 (or open); SPI MISO if D_SEL = 0 | Pin 20 | source Table 6 (p.15) | |
| RXD / SPI MOSI | Serial port in if D_SEL = 1 (or open); SPI MOSI if D_SEL = 0 | Pin 21 | source Table 6 (p.15) | |
| SDA / SPI CS_N | DDC data if D_SEL = 1 (or open); SPI chip select if D_SEL = 0 | Pin 18 | source Table 6 (p.15) | |
| SCL / SPI CLK | DDC clock if D_SEL = 1 (or open); SPI clock if D_SEL = 0 | Pin 19 | source Table 6 (p.15) | |
| TIMEPULSE | Time pulse (1PPS) | Pin 3 | source Table 6 (p.15) | |
| EXTINT | External interrupt pin | Pin 4 | source Table 6 (p.15) | |
| RESET_N | Reset input | Pin 8 | source Table 6 (p.15) | |
| V_BCKP | Backup voltage supply | 1.4-3.6 V | Pin 22 | source Table 6 (p.15); Table 10 (p.18) |
| RF_IN | GNSS signal input | Pin 11 | source Table 6 (p.15) | |
| LNA_EN | Antenna/LNA control (NEO-M8N) | Pin 14 | source Table 6 (p.15) |
Build with it
Project ideas for the NEO-M8N GPS module. Each link opens Soldr with the prompt filled in; Soldr assigns the pins, checks power and shows how to wire every part.
- GPS position display: The bare module's UART defaults to 9600 baud and its logic levels follow VCC (max 3.6 V). The breakout is undocumented, so power it at 3.3 V only unless it states otherwise.
- GPS clock: Pico UART pins are 3.3 V, matching the module's VCC-referenced levels. The breakout is undocumented, so power it at 3.3 V only unless it states otherwise. Use outdoors with a clear sky view; a cold start can take 26 s or more.
- Speed and altitude readout: The module's inputs are limited to VCC (Table 10), so pair it with a 3.3 V board such as the ESP32 rather than a 5 V board. Learning project.
Common mistakes
- Feeding the bare module 5 V: VCC absolute maximum is 3.6 V (source: link, Table 9 p.18); whether the listing board has a regulator is not covered by this document
- Wrong baud rate: the default UART setting is 9600 baud, 8N1 (source: link, Section 8)
- Expecting a quick fix: typical cold-start time-to-first-fix is 26 s or more, with all satellites at -130 dBm and a clear sky (source: link, Table 1 p.6)
Not covered by the official source
- Breakout board not covered by an official document.
- The listing antenna is not documented by u-blox; antenna figures are the module's recommendations only.
- Current figures are from Table 11, p.19.
- The listing breakout and the listing board's receiver chip are not documented; power the NEO-M8N at 3.3 V only unless the breakout states otherwise.
Sources
- link (NEO-M8 Data sheet UBX-15031086 R14, u-blox)